"Bart has come into her life like a whirlwind and has told her that heroin makes you forget. She's clinging onto that and once again she's reaching out to the wrong kind of people, so this is a downward spiral for Cleo."

Cleo has a reputation for being one of the show's good girls. Were you worried about losing that?

"I think it's good when you have a character like Cleo who is sensible but sometimes makes really bad decisions. We're pushing the limits with her by making her do really stupid and dangerous things.

"I was worried about all of the little girls who love Cleo and look up to her, but if the audience are watching her downfall and getting concerned about it, hopefully she's teaching them a lesson about the dangers of heroin."

"There'll certainly be more temptations for Cleo and she's obviously in a really dark place, so that does continue and it's not just over in an instant. As for whether Cleo takes heroin again, I'm not sure what they've got planned. But I do know these two innocent characters – Cleo and Joel – are getting increasingly wrapped up with Warren and Sienna."

Can you tell us about the research you did for this week's scenes?

"I watched some quite horrible videos on YouTube and I also researched the effects of heroin and how it makes you feel. Even for the scenes where Cleo had taken heroin the day before, I had to think about showing the comedown from that and how it makes your body feel.

"It's the worst hangover in the history of hangovers, so I had to keep that in mind when I was doing all of my other scenes. But I like a good challenge, so I enjoyed doing the storyline."

What kind of impact would you like this story to have?

"I think Cleo's problems all stem from the abuse that she's received in the past. We're reminding people that it's a long-lasting effect and it does follow you later on in life. It affects your decisions, your relationships and how you handle rejection.

"Even before this, Cleo was turning to alcohol. She's been getting drunk and I think when you start turning to substances to numb your pain, those substances end up getting stronger and stronger.

"Turning to heroin is obviously incredibly dangerous, but her cousin is on it too so it's accessible for her. But it's such a horrible life-destroying drug and it's shocking for the audience, because out of any Hollyoaks character, people really wouldn't have expected Cleo to get hooked on heroin."

"Yeah, he's lovely. While we've been working together, I've felt that we've had a really good chemistry. My first scenes were shouting at him over drugs so we were thrown into the deep end! But he's a really nice lad and we got on well."

It may be a bit controversial, but would you like anything to happen between Cleo and Joel?

"Well Joel is a priest and God is the love of his life, but I do definitely think something could be brewing between them. There's certainly a twinkle in her eye when she looks at Joel."

What's Rory (Joel) been like to work with?

"Absolutely lovely. He's got such a positive energy on set. He's always giggling in the middle of a take. I'm normally really professional, but he's got this amazing ability to push me over the edge so I can't stop laughing."

"We'd kept the whole thing top-secret and it didn't get leaked – Jared even went to his own funeral to keep it under wraps – so the response I got was that everyone was gutted. They felt a bit cheated that Nathan and Cleo never got together.

"People were really rooting for that, which is nice because it shows people are invested in the characters. But she's already onto the next thing now, she's over Nathan!"

So many characters around Cleo have left recently. Has that been weird for you?

"It is strange, because I came in with Kai Owen (Pete), Zoe Lucker (Reenie) and all of my on-screen sisters. I'm the only one left now, but the great thing about Hollyoaks is that it's just a big machine that keeps on going.

"New people are always being brought in and when people do leave, you're always so busy with your next storyline. But I think if Amanda Clapham, who plays Holly, goes I'll be very upset!

"Amanda, Parry [Harry] and Duayne [Zack] are the people I'm really close to. I'll feel like I've got no mates if they go, so they can't ever leave!"

Hollyoaks airs weeknights at 6.30pm on Channel 4, with first look screenings at 7pm on E4.